640 ELIOT BLACKW ELDER 



Cambro-Ordovician rocks were folded in the Gaspe Peninsula and 

 as far as northwestern Newfoundland. The belt of deformation 

 was apparently wide enough to include most of New Brunswick, 

 perhaps Nova Scotia, nearly all of Maine, and probably even Rhode 

 Island. The warpings and changes of level which accompanied 

 the folding affected a large part of the eastern interior of the 

 United States and doubtless Canada. These movements have 

 lately been summarized by Schuchert.'' In western United States, 

 however, there appears to be evidence of nothing more than a 

 change of relative altitude between the sea-level and the land 

 surface. 



Brunswickian (late-middle Devonian) . — -Although the folding of 

 the older rocks in eastern Canada, just before the deposition of the 

 Carboniferous measures, was well known to Logan, Dawson, and 

 other pioneer Canadian geologists, and is noted by Dana in all the 

 editions of his Manual, the event has received much less attention 

 than it deserves from geologists in general. Several of the more 

 recent textbooks of geology make no mention of the occurrence, 

 and it is sometimes ignored in discussions of Devonian paleoge- 

 ography where it is a factor of importance. Dawson's description,^ 

 although reflecting some provincial bias, may serve to call attention 

 once more to the importance of the Devonian disturbance. He 

 says in part : 



The whole surface of Acadia was thrown into a series of abrupt folds — great 

 masses of plastic granitic matter invading every opening in the shattered 

 masses. This period surpasses every other, in the geological history of the 

 eastern slope of the American continent, in its evidence of fracture of the 

 earth's crust. To this period we must refer the greater part of the intrusive 

 granites of Eastern America, and to it also is referable the greater part of the 

 metamorphism of the Silurian rocks, and the origin of the numerous metallic 

 veins by which these are traversed. 



As there appears to be in current use no name for this folding, 

 the term "Brunswickian" is suggested to meet the evident need. 



' Charles Schuchert, " Paleogeography of North America," Bull. Geol. Soc. Am., 

 XX (1908), 488-89. 



^ Sir WilHam Dawson, Geology of Nova Scotia, Neu' Brunswick, and Prince Edward 

 Island, 2d ed. (1891), pp. 665-66. 



